Show HN: I turned my iPhone and a $20 smart plug into an f-stop timer

I am a film photographer and do some darkroom printing and always wanted one of the proper, advanced f-stop timers, but never really wanted to spend a couple hundred dollars on one. Eventually I figured my phone was already perfectly capable of doing the timing, it just needed a way to switch the enlarger.

So I built Darkplug around a cheap smart plug. The app controls the enlarger over the local network and does regular timing, f-stop timing, test strips, has an intuitive dodge/burn workflow, split grade (2 timing channels) and paper development timing.

I’ve been using it for a few months in my improvised bathroom darkroom.

Fair warning: the app was blindly vibe coded using Codex and Xcode.